Professor Thomsen has a Masters in Linguistics and a Doctorate in PsychoLinguistics, and is the leading second language acquisition authority in the organization with incomparably far and away the most hours of linguistic fieldwork in human history. His "Growing Participator Approach" synthesizes insights from the best of second language acquisition, and is used in over 76 countries.

Look up "Growing Participator Approach" on facebook, and you'll find links to all his resources. Below is his "Iceberg Principle", which challenges the way we think about internalization of vocabularly in what I think is a wonderfully freeing and challenging way.

As you learn a new language, consider that the mass of new words, concepts, and cultural understandings form a sort of iceberg in your brain.
Near the upper tip of the iceberg, floating effortlessly above the surface of the water, are words that you use regularly and easily.

Down deep, at the base of the iceberg are those words which you recognize as words, but can only understand if you hear them in their original context.

Above them are those words you can understand with some contextual support.

Above them are the words that feel as thought they are on the tip of your tongue. Perhaps you have a sense of what the word starts with, how many syllables it has, what gender it was...

Above them are words you could come up but haven't needed recently.

Above them are words you have spoken once or a few times.

Finally, at the topmost tip of the iceberg, are the words that you can understand before the person finishes saying them.

Words move up in the iceberg through repeated exposure in which they are heard and understood due to context.

How To Make the Iceberg Work for Me

How many times have you been trying to come up with a word or phrase, and just couldn't? Then you heard someone else say it, and immediately said, "Oh, yeah, that's it!" and felt stupid because you hadn't been able to say it! Actually, you shouldn't feel stupid, but should be glad because you recognized the word, so it was in your mind somewhere -- now you'll be able to think of it more easily next time!

Many language learners put great energy into attempting to master every word fully as possible on first encountering it. They find that a large portion of the words they tried to master do not stay mastered. We find it works better to simply aim to put the words into the lower part of the iceberg and let them rise.

One person might expend great energy trying to put 300 words into the tip of the iceberg (the goal being to speak them out at will), to soon discover less than two hundred remain there. Another person, for the same expenditure of energy, might put a thousand words into the lower parts of the iceberg (the goal being to understand them when they are again heard in context), to soon discover that more than 200 of them have already risen to the tip of the iceberg. The latter language learner has achieved as much as the former when it comes to the words that are in the tip of the iceberg, but in addition, has another eight-hundred or so words in the iceberg, working their way up. The former language learner has only another 100 words lower in the iceberg working their way up.

The first time you hear and understand a word, it goes into the bottom of your iceberg. Then, as you hear and recognize the same word used in different contexts, it moves up in the iceberg. By the time you've heard it in about a dozen different contexts, it will have moved closer close to the top. You'll be able to use it now and then, and as you use it more, it will become part of the iceberg that rises above the water—words with which you are really familiar and comfortable using.

In our experience, most language learners find the iceberg principle a great encouragement. However, there are some who find it frustrating to apply this principle, and would prefer to learn less words, in order to feel a sense of greater level of mastery (at least they hope) of those they have attempted to learn. When working in accordance with the iceberg principle, they may express frequent frustration that they “can’t remember anything” when it is obvious to observers that they remember a huge amount (as they respond to words or can utter them after being reminded slightly). They just have a very strict standard for what they will count as something “remembered” - expecting instant ability to speak the word exactly right.

>Listen to tons of speech you understand so that you’ll keep encountering words in new contexts; as you re-encounter a word in a new context, it rises in the iceberg.

>Engage in lots of one-on-one interaction; this will also mean you’ll keep encountering words that need to rise, but also that you’ll find you need them—and use them—in your own speech.

>At more advance levels, in highly literate host languacultures reading becomes an extremely valuable activity both for initial encounters with new words, and for repeated encounters.

>Remember that if there are only a few weak words in your iceberg, your chances of re-encountering one while hearing speech you understand is low; if there are many thousands of weak words in there, then you’ll never listen for long to speech you understand without encountering some of them and having them rise. Massive quantity is key.

Tips For Tracking How Many Words Are In Your Iceberg

At the end of sessions with your language helper, have them note down new words they have been helping you with. This is your vocabulary log, and will prove invaluable as you measure your progress over the years. Each day, as you assess how your interactions in your host community have gone, also jot down new words you heard.